• 대한약학회:학술대회논문집
• /
• 대한약학회 2000년도 춘계총회 및 학술대회
• /
• pp.202.1-202.1
• /
• 2000

• 대한약학회:학술대회논문집
• /
• 대한약학회 2001년도 Proceedings of the Pharmaceutical Society of Korea
• /
• pp.219.2-219.2
• /
• 2001

• Toxicological Research
• /
• 제18권2호
• /
• pp.167-174
• /
• 2002

Historical control data have been shown to be valuable in the proper interpretation and validation of reproductive toxicology studies. The present data were compiled from rat fertility and early embryonic development studies conducted at Korea Institute of Toxicology during the 1994∼2001 period. These data were assembled in order to provide background information for the general and reproductive data collected in 11 fertility and early embryonic development studies using Sprague-Dawley rats obtain-ing from the Breeding Facility, Korea Institute of Toxicology, Korea. A total of 274 males and 274 females were used in these studies during the eight-year period. Parameters of fertility and early embryonic development included clinical sign, body weights, food consumption, organ weights, estrus cycle, copulation index, precoital time, fertility index, pregnancy index, sperm parameters, and early embryonic development parameters. Most of the values were comparable to the previous historical control data reported by other investigators. These data can be wed not only as a historical data base for the meaningful interpretation of data from reproductive and developmental toxicity studies, but also as a contribution to biological characterization of Sprague-Dawley rats.

• Investigative Magnetic Resonance Imaging
• /
• 제25권3호
• /
• pp.156-163
• /
• 2021

Recently, neuromelanin and nigrosome imaging techniques have been developed to evaluate the substantia nigra in Parkinson's disease. Previous studies have shown potential benefits of quantitative analysis of neuromelanin and nigrosome images in the substantia nigra, although visual assessments have been performed to evaluate structures in most studies. In this study, we investigate the potential of using deep learning based automatic region segmentation techniques for quantitative analysis of the substantia nigra. The deep convolutional neural network was trained to automatically segment substantia nigra regions on 3D nigrosome and neuromelanin sensitive MR images obtained from 30 subjects. With a 5-fold cross-validation, the mean calculated dice similarity coefficient between manual and deep learning was 0.70 ± 0.11. Although calculated dice similarity coefficients were relatively low due to empirically drawn margins, selected slices were overlapped for more than two slices of all subjects. Our results demonstrate that deep convolutional neural network-based method could provide reliable localization of substantia nigra regions on neuromelanin and nigrosome sensitive MR images.

• 한국콘텐츠학회논문지
• /
• 제16권8호
• /
• pp.132-146
• /
• 2016

본 연구는 한국형 수용태도 척도를 개발하고 이 척도에 대한 신뢰도와 타당도를 검증하는데 목적이 있다. 연구 1에서는 수용태도 척도를 개발하였다. 먼저 문헌조사 및 기존 연구들을 통해 예비문항을 추출하였다. 그리고 대학생 324명을 대상으로 개방형 설문조사와 심층면접을 통하여 수집한 문항들을 내용분석을 실시하여 총 24개의 예비문항을 선정하였다. 다음으로 대학생 355명을 대상으로 설문조사를 통하여 예비 문항의 신뢰도 분석, 탐색적 요인분석과 확인적 요인분석을 실시하였다. 그 결과 12개 문항을 최종 확정하였고 2개의 하위요인(외향적 수용, 내향적 수용)을 추출하였다. 연구 2에서는 새로 개발한 수용태도 척도의 타당화를 위하여 328명의 성인들을 대상으로 온라인 설문조사를 실시하였다. 새로 개발한 수용태도 척도와 자아존중감, 심리적 안녕감, 우울, 불안, 그리고 부정적 평가에 대한 두려움 척도와의 상관분석을 통해 수렴타당도를 확인하였다. 끝으로 본 척도 개발의 의의와 제한점, 후속연구를 위한 제언 등을 논의하였다.

• Journal of Pharmaceutical Investigation
• /
• 제37권3호
• /
• pp.179-186
• /
• 2007

A simple, sensitive and selective liquid chromatographic/tandem mass spectrometric method (LC-MS/MS) was developed and validated for doxifluridine and 5-fluorouracil (5-FU) quantification in dog heparinized plasma. Sample preparation was based on liquid-liquid extraction using a mixture of isopropanol/ethyl acetate (1/9 v/v) to extract doxifluridine, 5-FU and 5-chlorouracil (5-CU, an internal standard) from plasma. Chromatography was performed on a C-18 analytical column and the retention times were 2.7, 1.5 and 1.7 min for doxifluridine, 5-FU and 5-CU, respectively with shorter analysis time within 5 min than previously reported methods. The ionization was optimized using ESI negative mode and selectivity was achieved by tandem mass spectrometric analysis by multiple reaction monitoring (MRM) using the transformations of m/z 244.8>107.6, 129.0>42.0 and 144.9>42.1 for doxifluridine, 5-FU and 5-CU, respectively. The achieved low limit of quantification was 20.0 ng/mL and the assay exhibited linear range of 20-2000 ng/mL ($R^2>0.99957$ for doxifluridine and $R^2>0.99857$ for 5-FU), using $100{\mu}L$ of plasma. Accuracy and precision of quality control samples for both doxifluridine and 5-FU met KFDA and FDA Guidance criteria of 15% for accuracy with coefficients of variation less than 15%. This method demonstrated adequate sensitivity, specificity, accuracy, precision and stability to support the simultaneous analysis of doxifluridine and 5-FU in dog plasma samples in pharmacokinetic and bioequivalence studies.

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권6호
• /
• pp.2655-2661
• /
• 2012

Validation of a food frequency questionnaire (FFQ) utilising a short-term measurement method is challenging when the reference method does not accurately reflect the usual food intake. In addition, food group intake that is not consumed on daily basis is more critical when episodically consumed foods are related and compared. To overcome these challenges, several statistical approaches have been developed to determine usual food intake distributions. The Multiple Source Method (MSM) can calculate the usual food intake by combining the frequency questions of an FFQ with the short-term food intake amount data. In this study, we applied the MSM to estimate the usual food group intake and evaluate the validity of an FFQ with a group of 333 Korean children (aged 3-6 y) who completed two 24-hour recalls (24HR) and one FFQ in 2010. After adjusting the data using the MSM procedure, the true rate of non-consumption for all food groups was less than 1% except for the beans group. The median Spearman correlation coefficients against FFQ of the mean of 2-d 24HRs data and the MSM-adjusted data were 0.20 (range: 0.11 to 0.40) and 0.35 (range: 0.14 to 0.60), respectively. The weighted kappa values against FFQ ranged from 0.08 to 0.25 for the mean of 2-d 24HRs data and from 0.10 to 0.41 for the MSM-adjusted data. For most food groups, the MSM-adjusted data showed relatively stronger correlations against FFQ than raw 2-d 24HRs data, from 0.03 (beverages) to 0.34 (mushrooms). The results of this study indicated that the application of the MSM, which was a better estimate of the usual intake, could be worth considering in FFQ validation studies among Korean children.

• 한국콘텐츠학회논문지
• /
• 제14권3호
• /
• pp.269-276
• /
• 2014

본 연구에서는 라쉬분석을 통하여 한글판 학교기능평가(School Function Assessment)도구의 구성타당도, 척도 적합성을 검증함으로써 이 평가도구의 국내 사용을 위한 기초자료를 제시하고자 한다. 서울 및 경기, 충청 지역의 만 7세~12세(초등학교 1학년~6학년)인 98명 장애아동을 대상으로 아동의 보호자 및 담임 특수교사 또는 작업치료사와 직접 면담 또는 전화를 통하여 자료를 수집하였다. 자료분석은 라쉬분석을 통하여 단일차원모형(unidimensionality)에 대한 적합통계치(fit statistics)를 제시하였다. 또한, 라쉬분석의 평정척도모형(rating scale model)을 이용하여 평정척도의 적합성 분석을 실시하였다. 라쉬분석 결과 각 25개 하위척도 내 총 328개 항목 중 단일모형 적합통계치가 부적합한 항목은 Part II 과제지원 영역에서 총 4개였고, Part III 신체적 과제 영역에서 부적합 항목은 18개, 인지/행동적 과제 영역에서 부적합 항목은 14개 항목으로 나타났다. 한글판 학교기능평가 도구의 모든 평가 하위영역의 5점 평정척도는 적합한 것으로 나타났다 본 연구를 통하여 한글판 학교기능평가 도구의 구성타당도와 평정척도 적합성을 확인하였다. 그 결과 5점 평정척도는 적합한 것으로 나타났으나, 일부 부적합 항목이 발견되어 앞으로 국내 타당도 확립과 준거제시를 위한 연구가 추후 이루어져야 할 것으로 판단된다.

• 한국컴퓨터정보학회논문지
• /
• 제3권2호
• /
• pp.1-6
• /
• 1998

소프트웨어 개발 과정에서 신뢰성 평가는 대단히 중요하다. 테스트 단계를 구분하지 않은 소프트웨어의 신뢰도 평가˙분석의 결과는 신뢰성이 결여될 수 있다. 따라서 본 논문에서는 이러한 문제점을 해결하기 위해 테스트 단계를 구분하여 신뢰성 평가에 관한 연구를 하였다. 이를 위해 단위 테스트(Unit Test), 통합 테스트(Integration Test), 확인 테스트(Validation Test), 시스템 테스트(System Test)에서 발견된 결함 데이터를 이용하여 소프트웨어 신뢰도 성장 모델(Software Reliability Growth Model : SRGM)인 지수형, 지연 S자형, 습숙 S자형 SRGM에 적용하였다. 그 결과 단위 테스트에서는 습숙 S자형, 통합 테스트에서는 지연 S자형, 확인테스트에서는 지연 S자형, 시스템 테스트에서는 지수형 SRGM이 가장 적합한 것임을 입증하였으며, 신뢰성 평가 척도인 파라미터 추정, 편차 자승합, 기대잔존 결함수 등에서 본 연구의 결과가 기존의 방법보다 우수함을 보였다.

• 약학회지
• /
• 제52권2호
• /
• pp.93-100
• /
• 2008

A liquid chromatographic method with tandom spectrometric detection (LC/MS/MS) for the simultaneous determination of doxifluridine and its active metabolite, 5-fluorouracil (5-FU) was developed over the concentration range of $5{\sim}2000$ ng/ml, respectively. Doxifluridine, 5-FU and internal standard, 5-chlorouracil (5-CU), were extracted from liver and intestine tissue via protein precipitation. Acetonitrile was used as the extraction solvent and the supernatant was evaporated and reconstructed in mobile phase. Optimum chromatographic separation was achieved on a Agilent Zorbax $C_{18}$ ($100\;mm{\times}2.1\;mm$, $3.5\;{\mu}m$) column with mobile phase run in isocratic with methanol : water (20 : 80, v/v). The flow rate was 0.2 ml/min with total cycle time of 5 min. The lower limit of quantification was validated at 5.0 ng/ml of liver and intestine tissue, for both doxifluridine and 5-FU, respectively. The intra-day and inter-day precision and accuracy of quality control (QC) samples were <11% coefficient of variation and <7% relative error from theoretical concentration for both analytes. In addition, the special designed stability study was performed, because the metabolism of doxifluridine occurs spontaneously even in ice bath for monkey liver. The stability of doxifluridine in liver and intestine of monkey and beagle dog was compared. It was found that bioanalytical validation could not be performed for the monkey liver; however, beagle dog's liver has relatively low speed of metabolism compared to monkey liver and instead of monkey liver, beagle dog's liver could be used for the validation. Bioanalytical validation could be performed in monkey intestine. Eventually, this developed method for liver and intestine will be useful in support of the toxicokinetic and pharmacokinetic studies of doxifluridine and 5-FU.